Actuator for gates, doors and the like

ABSTRACT

An actuator for gates, doors and the like, with at least one wing. The actuating motor ( 14 ) and the associated motor reduction unit ( 15 ) are housed inside as half-arm ( 2 ) which turns on a fixed support ( 9 ) in an oscillating way about a substantially vertical swinging axis ( 10 ). Advantageously, the electric motor ( 14 ) operates a maneuvering worm screw ( 12 ) which is carried by said half-arm ( 2 ) and engages a corresponding helical gear ( 13 ) coaxial with the swinging axis ( 10 ) and is fastened to the fixed support of the half-arm ( 2 ) by a torque-limiting device which prevents excessive stresses on the actuator as a result of external forces and also makes it possible to release the helical gear for manual emergency actuation of the wing.

This application is a 371 of PCT/EP00/12408, filed Dec. 7, 2000.

The subject of the invention is an actuator for gates, doors and anyother similar barriers for closing entrances or openings with at leastone wing (rotating or sliding), or the like, the said actuatorcomprising an arm or half-arm or so-called actuator arm, hinged with itsrear end to a fixed support in an angularly displaceable manner, beingdisplaceable by means of an electric motor and a reduction unit. The armcan be an articulated arm having a so-called drawing arm articulatedwith its front end to the wing of the door, and with its rear end, bymeans of an intermediate folding articulated joint, to the front end ofthe actuator arm.

DE-U-295 13 302 discloses an actuator for a window with a rotating wing.The actuator comprises a foldable arm, which is hinged to a fixedsupport on one side and to the wing on the other side. An actuatingmotor and a reduction unit are arranged in the half-arm hinged to thefixed support and are operatively connected to the intermediatearticulation between the two half-arms.

DE-A-197 24 439 discloses an actuator for a bus door, wherein a clutchsystem is provided between the door swinging pivot and the coaxial gearto enable the door to be freely rotated in case of emergency.

The purpose of the invention is to provide an actuator which, as awhole, presents smaller overall dimensions, and the arm of which affordsgreater sturdiness so that it can be used as a stay for blocking thewing in the closed position, whilst it may also be installed onsupports, for instance, on supporting posts of small dimensions, in anycase preventing damage if the actuator half-arm were to be subjected torotational stress exerted by excessive external forces and enabling itsangular displacement by the said external forces in the direction ofopening and closing of the wing, at the same time making possiblerelease of the actuator half-arm from the respective operating motor foreasy manual emergency displacement of the wing.

According to one characteristic of the invention, the above purpose isachieved by the fact that the electric actuating motor and theassociated reduction unit are carried by the arm, preferably by theactuator half-arm and are preferably, housed in a correspondingly shapedand sized recess of the arm and preferably of the actuator half-armitself.

According to a preferred embodiment of the invention, the electric motoroperates, by means of the reduction unit, a manoeuvring worm screw whichis carried by the actuator half-arm and engages with a correspondinghelical gear coaxial to the swinging axis of the actuator half-arm, andis blocked, in a way so that it cannot turn, to the fixed support of theaforesaid half-arm itself.

According to another characteristic of the invention, the helical gearis mounted on the fixed support of the actuator half-arm by means of atorque-limiting device regulated in such a way as to enable rotation ofthe helical gear together with the associated worm screw, and hencetogether with the actuator half-arm, when the latter is subjected torotational stresses exerted by external forces greater than a pre-setmaximum allowable stress of the actuator half-arm itself.

Preferably, according to a preferred embodiment of the invention, thetorque-limiting device is also used to disengage the actuator half-armintentionally from its fixed support and so to enable its free and. easyrotation about its swinging axis when it is desired to displace the wingmanually about its oscillating axis in cases of emergency, for example,in the case of absence of electric current. For this purpose, accordingto the invention, the torque-limiting device set between the helicalgear and the fixed support of the actuator half-arm, as well as beingdisengageable automatically by the action of a pre-set maximum safetymoment exerted on and exerted by the actuator half-arm, is associated toreleasing means for pre-arrangement of the emergency manoeuvre which canbe operated manually, for example by means of a suitable, possiblyciphered, wrench and are designed to disengage and deactivate theaforesaid torque-limiting device.

Both the torque-limiting device and the releasing means associatedthereto for its manual disengagement in the event of emergency may bebuilt in a very wide variety of ways suited for the purpose.

According to a preferred embodiment of the invention, the helical gearis fixed to a gear casing on which the rear end of the actuator half-armis mounted, in such a way that it is free to turn, the said gear casingbeing in turn mounted, so that it is free to turn and is axiallysliding, on a hinge pin that is coaxial with the swinging axis of theactuator half-arm and fastened to the fixed support of the saidhalf-arm, whilst the torque-limiting device is made up of two toothedannular disks, which are set one on top of the other and are coaxialwith the swinging axis of the actuator half-arm, one of the disks beingfastened to the fixed support of the said half-arm, and the other beingfixed to the gear casing, the said annular disks meshing together bymeans of their ring gears which are set facing head-on to one another,the said ring gears being provided with radial teeth having inclinedsides, there being provided an engaging spring which exerts axial thruston the gear casing in the direction of mutual engagement of the twotoothed annular disks set on top of one another, consequently blockingthe helical gear, in such a way that it is not able to turn, to thefixed support of the actuator half-arm, but enabling mutualdisengagement of the two toothed disks by means of a correspondingmovement of axial yielding of the gear casing against the action of theengaging spring, and hence enabling jerking rotation of the helical gearabout the hinge pin as a result of a maximum pre-set torque exerted fromoutside, for example manually, on the actuator half-arm, and from this,by means of the worm screw, on the helical gear itself.

To enable manual emergency angular displacement of the wing and thecorresponding oscillating movement of the actuator half-arm on its fixedfulcrum, the two toothed annular disks of the above-describedtorque-limiting device are disengaged from one another, for this purposedisplacing the gear casing axially on the hinge pin against the actionof the engaging spring and by manually controlled releasing means, andkeeping the aforesaid casing in a position of disengagement of thetorque-limiting device, thus enabling the gear casing, and hence thehelical gear, to rotate freely together with actuator half-arm about theswinging axis of the latter.

Also the above mentioned releasing means for manual disengagement of thetorque-limiting device may be built in any suitable way whatsoever. In apreferred example of embodiment of the invention describe above, theaforesaid releasing means for manual emergency disengagement of thetorque-limiting device consist of a face cam mounted so that it can,turn manually between the gear casing or a part connected to the latter,consisting in particular of a part of the rear hinged end of theactuator half-arm, and the head end of the hinge pin fixed to thesupport of the actuator half-arm, the said cam presenting a profile suchas to enable, in one first angular position of the said cam, mutualengagement of the two toothed disks of the torque-limiting device by theaction of the respective engaging spring, whilst it displaces andwithholds, in a second angular position, the gear casing axially on thehinge pin and against the action of the engaging spring in a position ofdisengagement of the torque-limiting device.

In the preferred embodiment of the invention described above, both theautomatic disengagement and the intentional disengagement by manualemergency means for releasing the torque-limiting device set between thehelical gear and the fixed support of the actuator half-arm require alimited axial displacement of the gear casing, and hence of therespective hinged rear end of the actuator half-arm, on the fixed hingepin along the respective swinging axis.

Also this axial displacement of the hinged rear end of the actuatorhalf-arm may be enabled from a constructional standpoint in any suitablemanner whatsoever, even by means of corresponding allowances andtolerances. According to an embodiment of the invention, however, forthis purpose the intermediate articulated joint for folding of thefoldable arm of the articulated actuator or for the fixing to the wingand/or the joint articulating the drawing half-arm to the wing are madelike ball-and-socket joints or else like Cardan joints, with at leasttwo mutually orthogonal axes of articulation, one axis beingsubstantially parallel to the axis of oscillation of the wing, and theother axis being transverse to the half-arms, so enabling, when the gearis axially displaced on the hinge pin in order to disengage thetorque-limiting device, a corresponding inclination of the actuatorhalf-arm, and hence a corresponding axial displacement of its rear endwith respect to the hinge pin itself. For the same purpose, acorresponding ball-and-socket joint or Cardan joint may be provided alsobetween the gear casing and the respective end of the actuator half-arm.

These and other characteristics of the invention and the advantagesderiving therefrom will appear in greater detail from the ensuingdescription of an embodiment of the invention, which is illustratedmerely to provide a non-limiting example in the attached drawings, inwhich:

FIGS. 1 and 2 illustrate, as elevation and plan view, respectively, anarticulated actuator according to the invention applied to the wing of agate or door;

FIG. 3 shows the foldable arm of the articulated actuator in elevationand with the front part in longitudinal section;

FIG. 4 illustrates the foldable arm of the articulated actuator in planview and with the rear part in longitudinal section;

FIGS. 5 and 6 present a vertical section of the hinge of the rear end ofthe actuator half-arm to the corresponding fixed support, with thetorque-limiting device set between the helical gear and the fixedsupport in the engaged position (FIG. 5) and in the disengaged position(FIG. 6);

FIG. 7 is an exploded perspective view of the hinge of the actuatorhalf-arm to the corresponding fixed support;

FIG. 8 is a plan view of the articulated actuator in a particularcondition of stress by means of an external force exerted manually onthe wing;

FIG. 9 is a vertical section of the hinge of the rear end of theactuator half-arm to the corresponding fixed support, with thetorque-limiting device in the position of automatic disengagement by theaction of an excessive force of external stress;

FIG. 10 is a view of the actuator applied to a sliding wing; and

FIG. 11 illustrates a embodiment of the actuator having slidingconnection to the wing.

With reference to the drawings, the articulated actuator for gates,doors, or any similar barrier with at least one wing for closingentrances or openings, or the like, consists of a foldable arm 1 whichis substantially horizontal and comprises an actuator half-arm 2 and adrawing half-arm 3. The articulated actuator is applied to a gate or thelike, the wing 4 of which may be opened and closed by being turned abouta substantially vertical axis of oscillation 5. The rear end of thedrawing half-arm 3 and the front end of the actuator half-arm 2 arearticulated together by means of the intermediate articulated joint orpivot 6 for folding of the arm 1. This intermediate articulated joint 6for folding is made like a ball-and-socket joint or a Cardan joint withat least two mutually orthogonal axes of articulation so as to enable,in addition to folding of the arm. 1 about an axis that is substantiallyvertical and is parallel to the axis of oscillation 5 of the wing 4,also a limited mutual folding of the two half-arms 2 and 3 in asubstantially vertical plane, i.e., about an axis that is substantiallyhorizontal and transverse to the foldable arm 1. The front end of thedrawing half-arm 3 is connected by means of an articulation 7 to abracket 8 fixed to the wing 4, the said articulation 7 also being madelike a ball-and-socket joint or like a Cardan joint with at least twomutually orthogonal axes of articulation, so as to enable, in additionto the relative angular movement between the drawing half-arm 3 and thewing 4 about an axis that is substantially vertical and parallel to theaxis of oscillation 5 of the wing 4, also a limited mutual inclinationbetween the drawing half-arm 3 and the wing 4 in a vertical plane, i.e.,about an axis that is substantially horizontal and is transverse to thefoldable arm 1.

The rear end 102 of the actuator half-arm is hinged, as described ingreater detail later, in an oscillating manner about a swinging axis orpivot 10 which is substantially vertical and parallel to the axis ofoscillation 5 of the wing 4, as well as close to the said axis ofoscillation 5 itself, on a supporting bracket 9 fixed, by means of itsflange 109, to a post 11 or the like, and projecting horizontally fromthe said post 11 itself. The actuator half-arm 2 is made to oscillate inone direction and in the other about the swinging axis 10 by means of anirreversible turning pair consisting of a manoeuvring worm screw 12 anda corresponding helical gear 13. The helical gear 13 is coaxial with theswinging axis 10 of the actuator half-arm 2 and is blocked in anon-turning way to the fixed supporting bracket 109 by means of atorque-limiting device described hereinafter. The worm screw 12 engagedin the helical gear 13 is mounted in a turning way inside the actuatorhalf-arm 2 and is driven in rotation by a reversible electric motor 14by means of a reduction unit 15. The electric motor 14 and the reductionunit 15 are preferably mutually coaxial, as well as being coaxial withthe worm screw 12, and are housed inside the actuator half-arm 2, whichis for this purpose made hollow and is appropriately sized. In theexample of embodiment illustrated, the actuator half-arm 2 is made up oftwo complementary shells set on top of one another and connected bymeans of screws, of which one 16 is illustrated in FIGS. 5, 6, 7 and 9.In these figures, designated by the numbers 102′ and 102″ are the twoshells which form the hollow rear end 102 of the actuator half-arm 2 atthe point corresponding to the hinge of the said half-arm 2 to the fixedsupporting bracket 9. Designated by 17 in FIG. 4 is the supply cable ofthe electric motor 14. In these conditions, as the worm screw 12 isturned in one direction or the other by means of the electric motor 14and the reduction unit 15, which are integrated in the actuator half-arm2, given that the helical gear 13 is fixed, the actuator half-arm 2 isangularly displaced about the swinging axis 10 and causes the wing 4 tooscillate in a corresponding fashion, by means of the drawing half-arm3, in one direction or the other about the axis of oscillation 5, sothat the wing 4 is brought alternatively into an angular position ofclosing, illustrated by the solid lines in FIGS. 1 and 2, and in anangular position of opening, illustrated by the dashed lines in FIG. 2,whilst the foldable arm 1 folds in a corresponding way at theintermediate articulated joint 6.

In the embodiment illustrated, the hinge of the actuator half-arm 2 tothe fixed supporting bracket 9 comprises a hinge pin 18 which is coaxialwith the swinging axis 10 and is fastened to the fixed supportingbracket 9. For this purpose, the hinge pin 18 has a base flange 118, bymeans of which it rests on the supporting bracket 9 with interpositionof a centring ring 19 provided at the bottom with pins 119 which insertin corresponding holes 209 of the supporting bracket 9. The hinge pin 18has a threaded bottom end 218 which passes through the centring ring 19and through a hole 309 of the supporting bracket 9, and on which abottom locking nut 20 is screwed, which fixes the hinge pin 18 to thesupporting bracket 9. The supporting bracket 9 can have two or more setsof holes 209, 309 for fixing the hinge pin 18, so that the latter can bemounted as desired in different positions that may be more or less closeto the post 11 according to the dimensions of the post 11 itself andaccording to other particular requirements.

Mounted on the hinge pin 18, so that it is free to turn and to slideaxially, is a gear casing 21 which is fixed to the helical gear 13. Thesaid gear casing 21 is housed, in such a way that it can turn withrespect to the actuator half-arm 2 but is not axially sliding withrespect to the latter. in corresponding bushings 22′ and 22″ carried bythe two shells 102′ and 102″ of the end 102 of the actuator half-arm 2.The bottom shell 102″ of the said end 102 of the actuator half-arm 2 isopen at the bottom at a point corresponding to the respective hinge tothe fixed supporting bracket 9, whilst the said rear end 102 of theactuator half-arm 2 surrounds and embraces the helical gear 13 bothlaterally and at the top.

The gear casing 21 is connected to the fixed supporting bracket 9 (viathe centring ring 19) by means of a torque-limiting device made up oftwo toothed annular disks 23 and 24 which are set on top of one anotherand are coaxial with each other, as well as being coaxial with theswinging axis 10. These annular disks are fixed, one 23 to theunderlying centring ring 19, and the other 24 to the overlying gearcasing 21. For this purpose, the bottom toothed annular disk 23 of thetorque-limiting device has a ring of holes 223 in which correspondingtop pins 219 of the centring ring 19 insert, whilst in a similar ring ofholes 224 provided in the top toothed annular disk 24 of thetorque-limiting device, corresponding bottom pins 221 of the gear casing21 engage. The bottom toothed disk 23 of the torque-limiting device isaxially fastened to the base flange 118 of the hinge pin 18 by means ofa snap ring 33, whilst the top toothed disk 24 of the torque-limitingdevice is axially fastened to the gear casing 21 by means of anothersnap ring 34.

A pressure spring 25 housed in a top coaxial groove of the gear casing21 around the hinge pin 18 and acting between the gear casing 21 and aspring-seat nut 26 screwed on the threaded top end 318 of the hinge pin18 exerts axial thrust downwards on the gear casing 21 together with thetop toothed disk 24 of the torque-limiting device and maintains thebottom ring gear of this disk 24 engaged in the facing top ring gear inthe associated bottom toothed disk 23 of the torque-limiting device. Theteeth of the two ring gears, which are facing one another and aremutually engaged, of the annular disks 23 and 24 of the torque-limitingdevice extend radially and have their sides inclined in thecircumferential direction, as is evident from FIG. 7.

Between the pressure spring 25 and the spring-seat nut 26, a thrustbearing 27, for example of the roller type, is preferentially interposedin order to enable free rotation of the pressure spring 25 together withthe gear casing 21 with respect to the spring-seat nut 26 itself, whichis fixed to the hinge pin 18.

In the top part of the rear pivoted end 102 of the actuator half-arm 2,between the top end of the hinge pin 18 and an annular countercam part28 provided around a top central opening of the top shell 102′ of theactuator half-arm 2, is housed a face-cam disk 29 coaxial with theswinging axis 10. The said cam disk 29 rests with a bottom centralprojection on the head surface of the top end of the hinge pin 18,whilst on top it has a tubular central hub 129, by means of which it isguided, in a turning and axially sliding way, in the central opening ofthe annular countercam 28, which is fixed to the top shell 102′ of theactuator half-arm 2. The bottom annular surface of the countercam 28 andthe top annular surface of the cam disk 29 around its central hub 129are kept in contact together by the action of the pressure spring 25,which exerts axial thrust downwards on the gear casing 21 and, togetherwith the latter, on the entire end 102 of the actuator half-arm 2, andhence also on the countercam 28, with respect to the central hinge pin18.

The face-cam disk 29 can be turned about the swinging axis 10 by meansof a male wrench 30 which can be inserted in the corresponding non-roundhole 229 of the top central hub 129 of the cam disk 29 itself throughthe central opening of the annular countercam 28. The profile of thewrench 30 and of the hole 229 of the hub 129 of the cam disk 29 can alsobe provided with a ciphering. Instead of the non-round hole 229, the tophub 129 of the cam disk 29 may have a non-round pin which projects atthe top out of the end 102 of the actuator half-arm 2 through thecentral opening of the annular countercam 28, and on which acorresponding female wrench can be inserted. By means of the wrench 30and the hub 129, the cam disk 29 can be turned through a certain angleabout the swinging axis 10, for example position of emergency manualoperation of the wing 4, the cam disk 29 pushes the end 102 of theactuator half-arm 2 axially upwards on the hinge pin 18, raising ittogether with the gear casing 21 and against the force of the engagingspring 25 to such an extent that it disengages the top toothed disk 24of the torque-limiting device from the associated bottom toothed disk 23and keeps it in this disengaged position, as illustrated in FIG. 6. Inthis position, the torque-limiting device 23, 24 is disengaged, and thehelical gear 13, which is no longer blocked to the supporting bracket,9, can turn freely on the hinge pin 18 together with the gear casing 21.In this condition, therefore, the wing 4 may be opened and closedmanually about its axis of oscillation 5, and the foldable arm 1 isdrawn, i.e., folded, and distended by the wing 4 itself.

The above-mentioned axial displacements of the gear casing 21 and of thecorresponding end 102 of the actuator half-arm 2 are relatively smalland are enabled, in particular, by the ball-and-socket joint 6 wherebythe actuator half-arm 2 is articulated to the drawing half-arm 3, asdescribed previously with reference to FIGS. 3 and 4.

In a possible embodiment of the invention, which may used, for example,for leaves of a length of up to approximately 3 metres, the articulatedactuator is installed in such a way that, in the position of closing ofthe wing 4, the foldable arm 1 still remains at least slightly folded atthe point corresponding to its intermediate articulated joint 6, whilstthe wing 4 is blocked in the closed position by means of a lock, forexample an electric lock.

If in this position (or in any other intermediate position between theopening and closing positions of the wing 4 and when the cam disk 29 isin its above-described angular position of normal motor-driven operationof the wing, i.e., when the torque-limiting device is engaged and blocksthe helical gear 13 to the hinge pin 18 and to the supporting bracket 9,there is manually exerted on the wing 4, in the direction of opening orclosing, a pressure, which is indicated, for example, by the arrow A inFIG. 8 and which exerts pressure on the actuator half-arm 2 with acorresponding maximum allowable moment sufficiently smaller than themoment that could cause damage to the foldable arm 1 or to its hinge onthe supporting bracket 9, then the axial component of the pressurebetween the cooperating inclined sides of the teeth of the toothedannular disks 23, 24 of the torque-limiting device exceeds the axialforce of the engaging spring 25 and causes an axial displacement upwardsof the top toothed annular disk 24 together with the gear casing 21 andto such an extent that it disengages the said disk 24 from theunderlying fixed toothed annular disk 23, as illustrated in FIG. 9. Thetorque-limiting device 23, 24 is thus automatically disengaged andenables a jerking rotation of the gear casing 21 together with thehelical gear 12 on the hinge pin 18. The actuator half-arm 2 is thusrotated without causing damage about its swinging axis 10 by the actionof the opening or closing force exerted, in particular manually, on thewing 4, for instance in the event of an emergency represented by afailure of the operating motor or by an absence of electric current.

In order to prevent, in such cases of emergency, the need to exert onthe wing 4 the relatively large pressure necessary for disengaging thetorque limiting device, as described above with reference to FIGS. 8 and9, and when the hinge of the actuator half-arm 2 is accessible, it ispossible to disengage the torque-limiting device 23, 24 by turning thecam disk 29 by means of the wrench 30 and bringing it into its endangular position corresponding to the manual emergency operation of thewing 4, as described previously and as illustrated in FIG. 6. In thisposition, the actuator half-arm 2 is free to turn about its swingingaxis, and the wing 4 can be easily closed and opened by hand.

According to another possible embodiment of the invention, illustratedin FIG. 2 and used preferably for leaves having a length smaller thanapproximately 2 metres, the articulated actuator is installed in such away that its foldable arm 1 is distended completely in the closedposition of the wing 4; i.e., the centres of articulation 6, 7, 10 arealigned according to a straight line as illustrated in FIG. 2. Thisposition of alignment of the centres of the articulations 6, 7, 10 isdefined by cooperating detents 36, 37 provided on the two half-arms 2and 3. In this case, the foldable arm 1 of the. actuator functions, inits completely distended position, as a stay which blocks the wing 4 inthe closed position. The wing 4 may be opened at least partially only bymeans of the electric actuating motor 14, or else, in the event of anemergency, manually after the torque-limiting device 23, 24 has beendisengaged by means of the wrench 30 and the cam disk 29, as describedpreviously.

The above-described examples of installation of the articulated actuatoraccording to the invention refer to gates, doors or the like, with asingle wing. In the case of gates, doors or the like provided with twoleaves, which in particular may be blocked together by means of anelectric lock, the articulated actuator according to the invention maybe applied to both leaves in the same way as described previously withreference to FIG. 2 (foldable arm 1 distended in the position of closingof the wing), or else with reference to FIGS. 8 and 9 (foldable arm 1 atleast slightly folded in the position of closing of the wing).

According to a preferred embodiment of the invention, however, to one ofthe leaves, in general to the one opened last, an actuator is applied inthe way described with reference to FIG. 2 (foldable arm 1 completelydistended, with articulation points 6, 7 and 10 aligned with one anotherin the position of the closing of the wing), whilst to the other wing,in general the one that is opened first, an actuator is applied in theway described with reference to FIGS. 8 and 9 (foldable arm 1 still atleast slightly folded in the position of closing of the wing).

The articulated actuator according to the invention, among other things,presents the advantages described in that follows. The torque-limitingdevice 23, 24 set between the helical gear 13 and the fixed support 9 ofthe foldable arm 1 constitutes both a safety device against overloadingand damage by the action of excessive external forces, and a device forrelease of the actuator in order to enable emergency manual angulardisplacement of the wing 4. The said torque-limiting device makes itpossible to reduce the size and the cost of the irreversible manoeuvringturning pair made up of the worm screw 12 and the helical gear 13, andconsequently enables reduction also of the size and cost of thereduction unit 15 set between the said pair 12, 13 and the electricactuating motor 14. The above-mentioned reductions in size enable themotor 14 and the reduction unit 15 to be incorporated in the actuatorhalf-arm 2, or at least favours such an assembly, further reducing thecost and enabling execution of the articulated actuator as a compact,integrated constructional unit of reduced dimensions which does notrequire separate installation of the motor-reduction unit assembly andmay be installed also on posts or other supports of small size. At thesame time, the slight increase in the size of the foldable arm 1, anincrease which is necessary for the integration of the motor 14 and thereduction unit 15 in the actuator half-arm 2, bestows on the saidfoldable arm 1 a greater sturdiness and thus enables its utilization inthe completely distended condition as a stay arm for blocking the wing 4in the closed position, as described with reference to FIG. 2, sorendering an electric lock superfluous for this wing.

The various possibilities of installation of the articulated actuator ongates or doors with a single wing or with two leaves enable optimizationof its use and its adaptation to the various needs that may arise and tothe particular requirements of users.

In FIG. 10, the articulated actuator is applied to a sliding wing 4′. Asdisclosed above, the rear end of the drawing half-arm 3 and the frontend of the actuator half-arm 2 are articulated together by means of theintermediate articulated joint 6 for folding of the arm 1. The axis 6 issubstantially vertical and is parallel to the sliding plane of the wing4′.

FIG. 11 shown the articulated actuator according to the invention, withthe actuator half-arm 2 applied to the wing 4 (which may be opened andclosed by being turned about the axis of oscillation 5) by means of adrawing connection 3′ which is made of a carriage sliding on a guide 8′.

The front end of the actuator half-arm 2 and the carriage 3′ arearticulated together by means of the intermediate articulated joint 6.This intermediate articulated joint 6 for folding can be made like aball-and-socket joint or a Cardan joint with at least two mutuallyorthogonal axes of articulation, as disclosed above for the otherembodiments.

The rear end of the actuator half-arm is hinged, as described above, inan oscillating manner about the swinging axis 10 which is substantiallyvertical and parallel to the axis of oscillation 5 of the wing 4′, aswell as close to the said axis of oscillation 5 itself, on thesupporting bracket 9 fixed to the post 11 or the like.

What is claimed is:
 1. An actuator for operation of gates, doors orclosing barriers provided with at least one rotating or sliding wing,the actuator comprising an arm which is designed to be hinged to a fixedsupport at a swinging axis and connected to the wing, said armcomprising a first half-arm, which has a rear end designed to be hingedto the fixed support by a first pivot, so as to be angularlydisplaceable about said swinging axis, and has a front end hinged to aconnection to the wing by a second pivot, the actuator furthercomprising an electric actuating motor and a reduction unit, which arecarried by the first half-arm, wherein said motor and reduction unit areconnected to said first pivot for rotating the first half-arm about theswinging axis to move the connected wing.
 2. The actuator according toclaim 1, wherein the connection to the wing comprises a second half-arm,which is articulated with a front end to the wing and with a rear end,by an intermediate folding articulated joint, to the front end of thefirst half-arm, the first half-arm and second half-arm forming afoldable arm.
 3. The actuator according to claim 2, wherein one or bothof the intermediate folding articulated joint for folding the foldablearm and an articulated joint for articulation of the second half-armwith respect to the wing is a ball-and-socket joint or a cardan jointwith at least two axes of articulation which are mutually orthogonal,one axis being substantially parallel to the axis of oscillation of thewing, and the other being substantially horizontal and transverse to thefoldable arm.
 4. The actuator according to claim 2, wherein the actuatoris installed on a single wing provided with a lock, in a way whereby thefoldable arm still remains at least slightly folded in a position ofclosing of the wing.
 5. The actuator according to claim 2, wherein theactuator is installed on a single wing having no lock, in a way wherebythe foldable arm distends completely in a position of closing of thewing, so that the centres of hinging of the first half-arm to thecorresponding fixed support and of articulation of the second half-armwith respect to the wing, as well as of the intermediate foldingarticulated joint between said first and second half-arms, are alignedaccording to a straight line, whereby the foldable arm in the distendedposition works as a stay for blocking the wing.
 6. The actuatoraccording to claim 5, wherein a completely distended condition of thefoldable arm in the position of closing of the wing is defined byabutments between the first and second half-arms.
 7. The actuatoraccording to claim 1, wherein the swinging axis of the arm is close toand substantially parallel with an axis of oscillation of the wing. 8.The actuator according to claim 1, wherein the electric actuating motorand the reduction unit are housed in a recess of the first half-arm. 9.The actuator according to claim 1, wherein the electric actuating motoroperates, via the reduction unit, a maneuvering worm screw which iscarried by the first half-arm and meshes with a corresponding helicalgear coaxial with said first pivot.
 10. The actuator according to claim9, wherein the helical gear is fastened in a non-turning way to thefixed support of the first half-arm.
 11. The actuator according to claim9, wherein the helical gear is mounted by a torque-limiting deviceregulated so as to enable rotation of the helical gear together with theassociated worm screw, and hence together with the first half-arm whenthe first half-arm is acted upon in rotation by external forces greaterthan a pre-set allowable maximum stress.
 12. The actuator according toclaim 11, wherein the torque-limiting device can release the firsthalf-arm intentionally from the fixed support and thus enable free andeasy rotation of the first half-arm about the swinging axis when it isdesired to move the wing in cases of emergency or in the event ofabsence of electric current.
 13. The actuator according to claim 12,wherein the torque-limiting device, in addition to being automaticallydisengageable under the action of a pre-set maximum safety momentexerted on the first half-arm, is associated to releasing means forpre-arranging the emergency maneuver, which can be operated manually, byan appropriate ciphered wrench, and are designed to disengage saidtorque-limiting device.
 14. The actuator according to claim 11, whereinthe helical gear is fixed to a gear casing, on which the rear hinged endof the first half-arm is mounted in a turning way, said gear casing inturn being mounted so that it is free to turn and to slide axially on ahinge pin, whilst the torque-limiting device is made up of two toothedannular disks, which are set one on top of the other and are coaxialwith the hinge pin, one of said annular disks being designed to be fixedto the fixed support of said first half-arm and the other of saidannular disks being fixed to the gear casing, said annular disks meshingtogether by ring gears which are set facing one another head on and areprovided with radial teeth having inclined sides, there being providedan engaging spring which exerts axial thrust on the gear casing in thedirection of mutual engagement of the two toothed annular disks set ontop of one another, consequently blocking the helical gear to the hingepin in such a way that the helical gear is not able to turn, butenabling mutual disengagement of the two toothed disks by acorresponding movement of axial yielding of the gear casing against theaction of the engaging spring, hence enabling jerking rotation of thehelical gear about the hinge pin as a result of a maximum pre-set torqueexerted on the first half-arm and thereby, by the worm screw, on thehelical gear.
 15. The actuator according to claim 14, wherein the hingepin is coaxial with the swinging axis of the first half-arm and designedto be fastened to the fixed support of said first half-arm.
 16. Theactuator according to claim 14, wherein the two toothed disks of thetorque-limiting device can be disengaged from one another by emergencyreleasing means which may be operated manually and are designed toaxially displace and withhold the gear casing against the action of theengaging spring in a position of disengagement of the torque-limitingdevice, consequently enabling the gear casing, and hence the helicalgear, to turn freely together with the first half-arm about the swingingaxis.
 17. The actuator according to claim 16, wherein the emergencyreleasing means for disengaging the torque-limiting device consist of aface cam mounted, so that it can be turned manually, between the gearcasing or a part of the hinged rear end of the first half-arm, and thehead end of the hinge pin fixed to the support of the first half-arm,said cam having a profile such as to enable, in a first angular positionof the said cam, mutual engagement of the two toothed disks of thetorque-limiting device by the action of the respective engaging spring,whilst said cam displaces and withholds, in a second angular position,the gear casing axially on the hinge pin and against the action of theengaging spring in a position of disengagement of the torque-limitingdevice.
 18. The actuator according to claim 17, wherein the face camconsists of a cam disk held tight axially and elastically, by theengaging spring, between the head end of the hinge pin and an annularcountercam fixed to the first half-arm, said cam disk being turnablemanually by a wrench that can mate with the cam disk in rotation througha central opening of the annular countercam.
 19. The actuator accordingto claim 14, further comprising means that enable the rear end of thefirst half-arm to follow the axial displacements of the gear casingalong the hinge pin.
 20. The actuator according to claim 1, wherein thearm is connected to the wing by a carriage which slides parallel to theplane of the wing.
 21. A closing system for gates, doors, and barriersprovided with two rotating or sliding wings, which can be connectedtogether by a lock and each of which is operated by an actuatorcomprising a foldable arm including a first half-arm, which has a rearend designed to be hinged to a fixed support at a swinging axis so as tobe angularly displaceable about the swinging axis, and a secondhalf-arm, which has a front end designed to be hinged to a wing and arear end designed to be hinged to a front end of the first half-arm byan intermediate folding articulated joint, the actuator furthercomprising an electric actuating motor and a reduction unit, both ofwhich are carried by the first half-arm, wherein the actuator on onewing has a foldable arm that is completely distended when said one wingis in a closed position, so that centers of hinging of the firsthalf-arm to the fixed support, of the second half-arm to said one wing,and of the intermediate folding articulated joint between the first andsecond half-arms, are aligned according to a straight line, whereby thefoldable arm, while it is completely distended, operates as a stay forblocking said one wing, and wherein the actuator on the other wing has afoldable arm that remains at least slightly folded when said other wingis in a closed position.
 22. The closing system according to claim 21,wherein, during the opening the two wings from respective closedpositions, said other wing is opened first and said one wing is openedlast.